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A096937 Least k such that k*P(n)#/2 - 2 and k*P(n)#/2 + 2 are both primes, where P(i)= i-th prime, P(i)# = i-th primorial.

%I A096937 #6 Mar 29 2015 19:15:08
%S A096937 5,3,1,1,3,1,3,41,27,3,1,171,97,19,35,13,217,57,79,133,41,219,85,43,
%T A096937 477,205,35,455,635,275,2081,33,513,671,427,177,997,2671,601,123,525,
%U A096937 1139,411,479,363,1311,4685,109,159,3367,2761,257,161,137,49,393,3553,1807
%N A096937 Least k such that k*P(n)#/2 - 2 and k*P(n)#/2 + 2 are both primes, where P(i)= i-th prime, P(i)# = i-th primorial.
%e A096937 1*2*3*5*7/2 - 2 = 103, 1*2*3*5*7/2 + 2 = 107, 103 and 107 are both primes, so for n=4, k=1.
%t A096937 Primorial[n_] := Product[Prime[i], {i, 1, n}]; f[n_] := Block[{p = Primorial[n]/2, k = 1}, While[ !PrimeQ[k*p - 2] || !PrimeQ[k*p + 2], k++ ]; k]; Table[ f[n], {n, 50}] (* _Robert G. Wilson v_, Aug 19 2004 *)
%Y A096937 Cf. A060256.
%K A096937 nonn
%O A096937 1,1
%A A096937 _Pierre CAMI_, Aug 18 2004
%E A096937 More terms from _Robert G. Wilson v_, Aug 19 2004